TABLE 1. --Areas explored, 1950-60 



Beam trawl 

 ^ Gulf shrimp trawl 



samples of shrimp inhabiting the various 

 areas. 



Although commercial beam trawls are as 

 large as 40 feet, a 20-foot beam trawl was 

 used for these explorations to facilitate 

 handling. The beam trawl "D" frame was 

 constructed of 5/8-inch by 6-inch bar iron 

 and the net of 1 1/2-inch stretched^ mesh 

 cotton webbing (Ellson and Livingstone, 

 1952). 



* All net measurements are center of one knot to 

 center of next knot. 



A Gulf of Mexico shrimp trawl (Schaefers 

 and Johnson, 1957) measuring 41 feet 3 inches 

 along the head rope was first used in 1955-56 

 off Washington. It subsequently became the 

 major exploratory shrimp gear. The trawl 

 was attached immediately behind the otter 

 doors, which were fastened to a single warp 

 line by a 25-fathom bridle. Each otter door 

 was 2 1/2 feet high by 5 feet long. The net 

 was constructed of 1 1/2-inch stretched mesh 

 cotton webbing. 



During early cruises, attempts to locate 

 trawlable bottom were made by sounding 



